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Dekortage writes in with a new study by the National Center for Atmospheric Research suggesting that the North Pole may be clear of ice in summer as soon as 2040, decades earlier than previously thought. From the article: "'As the ice retreats, the ocean transports more heat to the Arctic and the open water absorbs more sunlight, further accelerating the rate of warming and leading to the loss of more ice,' Holland said in the statement. 'This is a positive feedback loop with dramatic implications for the entire Arctic.'"

Yes, which means the same mass takes more volume. When submerged ice (the majority of the ice in question) melts, it becomes more dense (same mass, less volume) which means it actually LOWERS the water level. Add in the amount of ice that is above water in the Artic channel, and the total change in water levels will be negligible.

Wrong again. The volume of the ice submerged in the water is equal to the volume of the ice if it were water. The only difference between the water and the ice is density. Ice is less dense. Because of that, it floats. But the only part of the ice that floats above the water line is the difference in volume between it's forzen and melted states. Submerged ice melting in water leaves the water level at exactly the same place. It's not a centimeter, millimeter, or even nanometer different. It physically can't be different.

Exactly. If you melt _only_ the ice that is below the water line, you will have less total volume than you did with the ice. If you melt _only_ the ice that is above the waterline, you will have more total volume than you did with the ice. If you melt _all_ of the ice, both above and below the waterline, you will have virtually the same volume. I say virtually and negligable because there will be other effects that take place in the real world that also affect local sea level. Not a huge amount mind you, bu

If you melt only the ice that is above the waterline there will be less ice below the waterline as the whole iceberg now weighs less and displaces less water to make it buoyant. You can't meaningfully melt only the ice above the waterline (or below the waterline). Your thought experiment is like saying: cut the top off the iceberg and hold the remaining portion of it down in the water using exactly the same force as the top of the iceberg used to exert, then melt the top of the iceberg and look at what happ

uhg, my inability to express this analogy is frustrating me. Your first paragraph is what I was posting about. If the only change enacted on the environment is to melt either the submerged, or non-submerged ice, and no other effect is allowed.While I was writing it, I was applying the logic such that you could replace the submerged half of the formula with dry land. If you break it out into two sperate formulas (submerged ice melting reduced total volume, non-submerged ice melting increases total volume) an

That's not entirely true either. Fresh water is slightly less dense than salt water. So when the ice cap melts, the oceans will become fresher and less dense. Since the overall mass of the water+ice does not change, the sea level will rise slightly.

Actually, no. Sea level will still rise: though only by a little. The water from the ice is less dense than the sea water around it because the sea ice typically contains less salt. Hence, more floats up above the water than bouyancy would suggest, which reduces the water level as it gets frozen, and increases the water level when the ice melts again.

Must admit I accepted this too until the argument was put to me recently. Fact is of course that the ice is fresh water (less dense) than the sea water it floats in. Check out the links posted elsewhere to physorg about this. Archimedes principle is about the force of the ice pushing down and displacing an equal weight of sea water. But since the ice is lower density then the volume of sea water displaced is less than the volume of the fresh water in the ice... even after melting. So when floating ice melts in sea water the sea level goes up. Check here [physorg.com], not just the reasoning but also the actual experiment to prove it.

Most of the ice volume is on land.It doesn't all have to melt to raise sea levels as they found out in antarctica. An Ice damn broke away, and a huge land-locked ice field moved into the water (ice can flow under pressure -- it just flows very slowly). Thus before 2040, the could be a lot of sea level rise before all the ice melt -- depends upon geography.

From what I'm reading, the Greenland ice sheets are only a few degrees above freezing at ground level due to geothermal heating. So -- it's going to make

Not really - he said something contrived and roundabout, that could be interpreted multiple ways. There are much simpler and more elegant ways to state the underlying physics without making goofy arguments about this term balancing that term.

Wow, way to tack a COMPLETELY UNRELATED comment onto mine, since it's near the top of the discussion, and hope for an easy chance at higher moderation.I made no arguments for or against global warming - I made a simple statement about the physics of ice melting.

And wow, you learned that electrical fields affect the motion of particles while studying particle physics, did you? I learned it in high school with everyone else. And you BELIEVE that Earth's magnetic field shields us from radiation? Why, that's

The GP's post looked familiar to me (the odd spelling of Jupiter), so I checked and sure enough the format [slashdot.org] of his cut and paste spam is getting better but the content is still just as silly. I think alot of the crap he quotes was originally generated by the psuedo-scientific "electic universe theory".

IMHO, the remnants of the anti-AGW crowd have now evolved into a run of the mill anti-science crowd. In the past I have found this mythbusting search [realclimate.org] an excellent resource, but I doubt this guy's skeptisim i

RTFA- Atmospheric CO2 or even methane has NOTHING TO DO WITH THIS FEEDBACK LOOP, except maybe for starting it. You could kill off every cow on the planet, shut down every CO2 producer, and the arctic ice would STILL be gone by 2040- because the cause (ocean absorbing more sunlight than ice) is a positive feedback loop that has already started.

In other words, the argument is over, global warming is happening, and it's far too late to play the blame game.

I've been following global warming for a long time now doing a lot research on the side for the last couple of years. Here are some facts about global warming. Some of which you hear and don't hear from the main stream media:
1.) The world appears to be getting warmer with many computer models showing an increase in global temperature.

The word you're looking for here is "thermometers".

3.) Apparently, the Earth magnetic field has decreased by 10% in the last 150 years (source: http://www.space.com/scienceastronomy/earth_magnet [space.com] ic_031212.html). I'm an electrical engineer and during my studies in particle physics, I learned that a particles velocity can be affected by magnetic fields. I believe it's possible that more of the Sun's radiation is penetrating the Earth's magnetic field due to it being weaker. If more radiation hits the Earth, shouldn't that also increase the overall temperature of the Earth and can global warming be attributed to this?

No, obviously not. The temperature was falling throughout those 150 years and has only started rising recently. The only correlated factor is CO2.

Complete crap. We have absolutely no idea what the temperature history of the other planets is and so we have no way of drawing any conclusions from any changes we see.

6.) The United Nations found that there is more Methane produced from livestock, which raises global temperature greater than CO2 by a factor of approx. 20, than any human caused CO2 combined (source: http://www.fao.org/newsroom/en/news/2006/1000448/i [fao.org] ndex.html)

The article you linked to says that CH4 only amounts to 18% of CO2-equivalent emissions. Since the lifetime of CH4 is only 12 years, the cumulative effect is smaller still.

How can you explain the recent same climate changes on different planets? I doubt it's all those cars being driven there.

See above. However, since temperatures on Earth have only started rising recently, and we've been monitoring the Sun's output longer than that, we can be sure the reason isn't a change in the Sun.

Is it possible that the warmer temperatures that Earth is experiencing are caused by cyclical natural phenomena? What about glaciers in Greenland that have been shrinking for 100 years (source: http://www.breitbart.com/news/2006/08/21/060821191 [breitbart.com] 826.o0mynclv.html [breitbart.com])? Also, how do you explain huge ice ages on Earth? Were thse caused by huge carbon emissions or was it a small natural climate cycle that just happens? Were those climate changes, which are no doubt more extreme than what's going on now, caused by the combustion engine? I don't have answers and everyone seems to have an opinion including a Nobel laureate who says the answer is more pollution (source: http://www.cnn.com/2006/TECH/science/11/16/smog.wa [cnn.com] rming.ap/index.h

2.) Tying a trend to warmer temperatures based on older data from the early 1900's is suspect at best. Good, reliable, accurate scientific equipment that measures the temperature wasn't readily available until recently (late 1900's).

This is why we use proxies to determine the temperature back then. There multiple datasets ranging from ice cores (we match the variations in atmospheric concentrations in more recent periods, and use the cores as a proxy to earlier dates), and tree ring data and so on. We generally don't use temperature records from early 1900s for precisely the above reason.

If more radiation hits the Earth, shouldn't that also increase the overall temperature of the Earth and can global warming be attributed to this?

But its different kinds of radiation. Magnetic fields affect charged particles only - aka solar wind and the aurora, and these have negligible energy input, especially relative to normal EM radiation which GW is about. Now, additionally, we have good data recently on the trends in both solar radiance and temperature forcing, and numerous papers have concluded that the sun itself can explain at most 30% of the observed trend. (Google scholar for the relevant papers)

Now, what do you think the orbital period of Jupiter around the sun is? Wikipedia has an answer 4333 days = 12 years. So, how interesting it is that we are seeing changes on the same time frame as Jupiter's passage around the sun, a passage that of course is not perfectly circular, in fact getting closer and further from the sun as time goes on...

What's more, there's another major factor - Jupiter's colour. Huge tracts of Jupiter's surface are in different colours, and as these vortices move about, obviously that is going to change its irradiance. Fortunately, Earth is not one big hurricane.

5. This is similar to Jupiter. Mars has an orbital period of 2 years, and has much greater eccentricity than Earth in its orbit. The temperature trend we have is over 3 years, a 1.5 cycles, something like between winter this year and summer next year. How mysterious that there would be a warming trend.

6. That source doesn't say that. Go read it again. Methane is more powerful per volume, and agriculture as a whole takes up more than transport. But transport isn't everything and the total volume of methane is small. Campaigners focus on transport, because transport is easier to cut than agriculture without killing bazillions of people.

Were those climate changes, which are no doubt more extreme than what's going on now, caused by the combustion engine?

They aren't. They happened over thousands of years and can be explained by a variety of other factors, whilst the current change is happening over decades and there is no other observed factor that can explain it.

I've been following global warming for a long time now doing a lot research on the side for the last couple of years.

No, you haven't. You are a liar. You've been listening to ultra-rightwing propaganda lies and you're happy to parrot them blindly and unreflectedly. That's a difference.

Many have pointed out the utter absurdity of your gibberish. Here's a couple more examples:

2.) Tying a trend to warmer temperatures based on older data from the early 1900's is suspect at best. Good, reliable, accurate scientific equipment that measures the temperature wasn't readily available until recently (late 1900's)

Shackleton recorded the annual extent of sea ice around Antarctica. We've been doing this for close to 100 years now. This IS a measurement of global temperatures.

Every harbor in the world keeps a record of the annual high-water mark at least since the British Empire. Every harbor in the world has seen the ocean levels rising for at least the last 100 years. This IS a measurement of global temperatures.

Weather related damages to the US agriculture (floods, droughts, hurricanes) have been tracked since Jefferson's time. This IS a measurement of global climate.

I'm an electrical engineer and during my studies in particle physics, I learned that a particles velocity can be affected by magnetic fields.

You might want to call Joe's Diploma Emporium and ask for your money back: magnetic force (and thus acceleration) is always perpendicular to the velocity of a charge. No amount of magnetic fields can increase or decrease the speed of a charged particle (and certainly not an uncharged one).

Jupitor [...]

In all your thorough research, you've never come across the name of this planet in printed form? Even once?

Is it possible that the warmer temperatures that Earth is experiencing are caused by cyclical natural phenomena? What about glaciers in Greenland that have been shrinking for 100 years

Wait - didn't you just tell us not to believe any temperature indicators that are 100 years old?

Were those climate changes, which are no doubt more extreme than what's going on now,

You are so utterly mentally retarded that it hurts my teeth to read your drivel. NEVER in the history of the earth has anything happened that was even a tiny fraction of what we are seeing today. Not only were the ice ages NOT "more extreme", they were peanuts compared to what we see today. We have a pretty decent record of global temperatures for several hundred thousand years and there is no indication anywhere of global temperatures changing on the time-scales of decades or even centuries. Nothing like what we're seeing right now can be found anywhere in the earth's climate record.

I recommend that you refrain from posting about issues you do not have the shimmer of a clue about.

I believe GP was merely pointing out that industrial machinery isn't the only possible source of strong temperature-affecting emissions. In either case, human activity is (theoretically) to blame, but it's not the human activity that many environmentalists want to blame.

The first is what could inhibit the Atlantic Conveyor by weakening its motive force : the downward flow of cooled salty water would be disrupted by large quantities of freshwater runoff from Greenland. Consequence - European weather becomes more like that on Newfoundland.
The second mechanism is what will cause sea levels to rise - the average temperature of the ocean is more than 4C so an uniform increase in water temperature will cause expansion. As the ocean is quite deep in places, a small expansion could lead to a significant rise in water level.
Admittedly not everybody cares about polar bears drowning or European climate becoming too cold to make Champagne or low-lying island states in the Indian Ocean being obliterated. Selfish gits.

If what you said was true large portions of the earth should be underwater every summer.

When it is summer in the North, it is winter in the South- so it stays relatively in balance up until now.

The difference is, the South has a rather big landlocked continent- as it's ice melts, it freshens the ocean, but doesn't change the heat absorption. The North is an ocean under the ice- when it melts, it absorbs more heat, thus creating TFA's feedback loop. So what YOU say might be true within the next 34 years

How does this get modded insightful? Have you EVER heard how buoyancy works? This is high school physics stuff, people - a floating object displaces exactly the same amount of liquid as it weighs - a floating ice cube that weighs a gram, displaces exactly one gram of water. It sticks up out of the water however much it needs to make this happen. When it melts, the gram of ice cube becomes a gram of water, which now changes the water level by exactly ZERO.Of course, in real life there are very subtle poi

I assure you my comprehension of high school physics is not in question;) My ability to express that knowledge using the english language (I claim Pascal as my native tongue:P) can most definately be questioned.If you melt _only_ the sumbmerged ice, the water volume will decrease. If you melt _only_ the ice above the water, the water volume will increase. Obviously this is not actually possible to do, I was attempting to express that the melting of ice over water does not matter as the total change is neg

Of course, in real life there are very subtle points about salinity to take into question

Another subtle real life point to take into account is that if the artic ice is melting, then probably the same thing is happening to antartic ice. Much of the antartic ice is on land, not water, and so is not currently displacing water. It will add to the ocean's level when it melts.

True, but that doesn't, in and of itself mean much. Sea water is salty, but ice generally doesn't contain much in the way of salt. So, you effectively have two somewhat distinct substances sitting on top of each other, rather than just two forms of water. What's more, maximum density is at less that 4 C. So, once it warms past that point, the water will start expanding enough to effect sea levels. Also, there is a lot of ice sitting atop the sea level. These facto

Because of bouyancy, melting the ice which is floating in water will not raise sea level. The ice is less dense than water, ergo it floats on the water, but it displaces an amount of water equal to its mass. So when it melts into water, the level will stay the same.You can try this yourself with a glass of water and ice cubes. Mark the water line with the ice cubes floating, then let the ice melt and notice that it hasn't moved. This is elementary school physics.

You can try this yourself with a glass of water and ice cubes. Mark the water line with the ice cubes floating, then let the ice melt and notice that it hasn't moved. This is elementary school physics.

I was thinking for some dumb reason that the ice cap would be frozen salt water.

Well, taken literally, that is true. The problem is that when salt water freezes, most of the salt is left behind. The explanation is fairly simple: The water starts forming crystals, and the salt (mostly Na and Cl ions) don't fit into the crystal structure very well. So at the surface, the water molecules slowly join the growing crystal, while the dissolved salt ions don't. You do get some salt in the ice, because ice usua

I haven't done the calculations, but I've read from a reasonably reputable source, New Scientist, that the Antarctic contains enough water to raise the world's oceans 75 meters. I suspect at some temperature, thermal expansion of the ocean would be greater than 75 meters, but I'm guessing, from other stuff I've read, that it'd take more heat to do that, than to melt the Antarctic. In other words, for a small worldwide increase in temp, I think the melting Antarctic would be the dominant effect.Of course,

Because not all of the ice is floating. There is a significant amount of ice in the Greenland Ice Cap. Melting of this will cause the sea level to rise. Interestingly, it will also cause Greenland itself to rise by a small amount due to the release from the weight of the ice. There is also non-floating ice on the Canadian Shield islands. In addition, if you assume that melting of the Arctic ice cap will be accompanied by at least some melting of the Antarctic cap, there could be a sea level rise of from a few meters to several meters. This is enough to cause a severe disruption of human populations.

Heat can be transfered away much more quickly by the flow of water around the floating ice than it can by just the air around the landlocked ice. I would think that the floating ice would melt much sooner.

This is a tipping point. It doesn't matter if global warming is manmade or a natural cycle. Cutting your carbon emmissions will not stop this feedback loop. Once reached, this feedback loop will continue until all the ice is melted during the summer, and there is NOTHING we can do about it with current technology.

I've heard that even though it is calving a lot of icebergs these days, it's getting enough snowfall that the total ice in the antartic is actually increasing. It's just increasing in a different place than the icebergs are coming from.

Besides, once you melt the ice there isn't much land left, and it's not very good real estate. But at least there is land under all that ice and snow, unlike in the arctic.

Say what you want, but I'm quite skeptical of their ability to accurately forecast this stuff...haven't there been sensationalist reports like this for the last 40 years? All of which were disproven when more accurate methods of forecasting came around?

Say what you want, but I'm quite skeptical of their ability to accurately forecast this stuff...haven't there been sensationalist reports like this for the last 40 years? All of which were disproven when more accurate methods of forecasting came around?

If I'm bleeding to death, the fact that the knife wounds are bleeding out faster than the gunshot wounds, and the fact that in the past I've gotten nosebleeds, so its not unusual for blood to be coming out of my body isn't really all that important. Dealing with the blood loss is.

So, on the one hand you have scientists reporting on melting icecaps, changes in weather patterns, and gross ecological damage. On the other hand, you have the Fair and Balanced(TM) network reporting random crap to refute the scientists. Sure, that balances out!

Even if cows are responsible for the production of more greenhouse gases than "industrialization" and automobiles (doubtful, but I'll argue with it anyway), the fact remains that animal agriculture *is* a man-made industry - thousands of years ago, people did not have mass-production farms that we have today. Regardless whether it's industrialization, cars, or mass-production agribusiness that's causing the problem, the real source is the same: human activity.

Even if cows are responsible for the production of more greenhouse gases than "industrialization" and automobiles (doubtful, but I'll argue with it anyway), the fact remains that animal agriculture *is* a man-made industry - thousands of years ago, people did not have mass-production farms that we have today. Regardless whether it's industrialization, cars, or mass-production agribusiness that's causing the problem, the real source is the same: human activity.

>haven't there been sensationalist reports like this for the last 40 years?

So look at the science and ignore the sensationalist reports. They're not sitting around speculating, they're measuring sea ice. Use your own critical thinking skills too. How much evidential weight should a Fox News opinion piece get that doesn't have a link to the report it talks about?

I'm pretty agnostic when it comes to global warming (usually arguing against it because someone has to) and I recently began to wonder what the consequence of a (very small) error would be in a computer simulation. Suppose that you (as a climate researcher) underestimated the effect that a warming trend caused by CO2 would have on plant growth, or overestimated the impact of CO2 on warming; in this situation wouldn't your model come to an equilibrium point much earlier and much higher than would be the case

This is why most studies don't use just one model. We typically use several models, each using different feedbacks to test their impact on the model. Even if two models do use the same physics, they may have slightly different schemes for handling them (ie cloud physics is particularly tough). Most published climate predictions are ensemble predictions, the average over many different models predicting the same thing. This tends to smooth out biases one particular model or another may have. Typically,

There is a slight difference in the academic and scientific quality between the reports appearing in major scientific journals that note the correlation between record high levels of CO2 in the atmosphere and increasing global temperatures, compared to the sort of "research" that appears on Fox news.

The story appeared on "Fox news" in the USA, and references a story appearing in the British newspaper "Daily Telegraph", both of those news organisations are known to be the main global warming deniers in each of those countries. They both love running sensationalist, unscientific articles in order to discredit the real scientific research going on.

There were predictions back 40 years ago. Oh, things like ozone holes, stuff like that. NASA eventually started looking for them, but had some trouble at first. The holes were so f*** large that their computer software was rejecting them as impossible.

I guess that 40 years ago, it would have been within the knowledge and ability of people to predict that cutting down the forests in Africa would cause a drought. Certainly, it's indisputable that humanly-deforested regions have suffered longer, more severe droughts since being deforested than at any time prior.

In recent years, there has been strong evidence that zooplankton levels are inversely proportional to temperature - cooler weather, more plankton; hotter weather, less plankton.

Does this mean that global warming is real? Define real. The globe is warming, that's irrefutable. Is it caused by human activity? Well, define activity - are you including deforestation, pollution, changes in the biological infrastructure of the planet, etc? Or just a select set of these? Also, and this is the billion dollar question, how much does the cause matter? If the planet is warming to the point where the current life is incapable of survival, who gives a damn about the causes? The latency inherent in the system is on the order of decades to centuries - changing the causes today won't be fast enough to stop the planet overheating, even if all causes WERE under human control. Why not take care of the problem right now and address the causes when we've got time?

I do believe humans are the primary cause, because although natural sources are often much greater, they are much more sporadic and much more regional. Humans have generated non-local sustained inputs, and those simply didn't exist before. Nor is the process linear. Not even remotely close. Saying that X is greater than Y by a factor of Z is only useful if you can use Z to make some useful observation. If the system is non-linear with both positive feedback and negative feedback loops that are themselves non-linear, you have what is known as a chaotic system. Chaotic systems have two properties - they are acutely sensitive to initial conditions, so any error in measurement will explode out of all proportion in almost no time at all, and they are non-differentiable, so that you can't accurately solve any given step even if you DID know the initial conditions. This means that you cannot directly equate human activity with natural activity and hope to get useful results. The best you can do is equate mechanisms and distributions to see what MIGHT be comparable.

However, my opinion of human activity is of no consequence. If humans cut out all pollution tomorrow, we would not start to see the benefits until a hundred or so years after global warming reached crisis point. If you want to do something effective, don't target the stuff that is pointless. Fixing human activity is like re-wallpapering a house that's on fire. Some things can be left to later.

Here's the thing. I doesn't matter if you are skeptical of the particular facts of a particular study. Even if you completely ignore global warming, the fact is that pollution is bad no matter how you slice it, and reducing it is a good thing no matter what your motivation is.

You are buying into the Corporate PR machine that is actually keeping the focus on debating how real global warmimg may or may not be so they can continue to delay the costly adjustments that they will eventually need to make to protect the environment. The problem is that the continued delay as we continue to spend time rebuffing their continual denials and half truths about global warming will make it less and less likely that we can do anything about it.

Global warming is real, and the only reason anyone expends energy denying it is because they don't want to pay to fix it. Do you think all these scientists from all these different countries are making up all this data just so they can stick it to the corporations? They have better things to do!

Exactly what do you need to become "convinced", and afterwards, what then? If you'd just throw up your arms, then you're not adding anything to the conversation.Sure, there have been sensationalist *and* rational reports like this for 40 years... and now we're watching the forecasts begin to noticably pan out. The bitch of it is that back when the effects weren't far above the noise level, the powers that be claimed "we don't see it", whereas now they're saying "we can't afford to do anything about it."

Yes!!! That is why Slashdot should fire Zonk immediately. Not soon...not tommorrow...now as soon they can sign the pink slip, NOW!!! I will continue to champion this message until the community sees the devastation his witless choices for articles have on our IQ's.

I'm writing from the future to tell everyone that the polar ice caps melted in 2045, and Atlantis was found underneath what was once called the North Pole. The earth's magnetic poles are in the middle of swapping, so it's about 135 degrees Fahrenheit there today.

The liberal moonbats are at it again. They're using all this "science" to provide us with "answers" about things which are essentially unknowable. And why? It's a vast liberal conspiracy that is meant to try and gain the hearts and minds of the weak willed and fey. But we modern conservatives are made of stern stuff!! We don't need "science" to tell us about the world around us. We use what's right in front of us: reality. If global warming WERE happening, which it isn't, it should be warmer outside today than it was in the past at this time of year. And even then, those liberals spin everything and flip-flop. You tell them that it's actually colder and they say that's a sign of global warming! What tricksters!! Well thankfully, the world has joined the conservative party and after the landslide win for Bush in 2004, it's obvious that things are NEVER going back. Don't believe in the lies that the liberals tell you or try to scare you with. It's purely scare tactics of a dying belief system. Instead, accept that as rugged individualists, we in the conservative parties will triumph over any adversity. We are strong. We are adaptable. Even IF global warming were happening WHICH it isn't, business would build special suits, vehicles and housing and create new materials to live on a hotter planet. The market will decide! And besides, my Enron stocks are way up there today. Thanks Cheney!:)

I've noticed that there are certain people (Almost always of the type that read slashdot, intelligent often engineer types) that are triggered by certain topics into discussions that start to remind me of those given by the religious (although these people tend to not be religious and are actually quite logical).

The main subject that really gets them riled is nuclear power. They get extremely upset at the concept of nuclear bans and will tell you, in detail, exactly why no alternative can work.

Another subject (I wonder if it's the same people, or just the same type of people with different trigger subjects) is this "we are changing/aren't changing the atmosphere). They are very passionate about how it's not us changing the world, coming up with a huge volume of reasoning (look around the threads in this discussion for some examples).

A third is free market--how regulation is the cause of all Americas financial woes.

The interesting thing is, in all cases nothing is really lost by being careful and taking some time to make sure we really are right. There is no reason to be so upset by the thought of keeping companies from opening nuclear plants across the US (Well, unless that's what you do for a living), but there are HUGE potential problems if not done correctly, meaning without enough regulation (we've all seen companies cut corners on safety when it effected profits).

Same with the environment. Religious folks aside (that's not the people I'm talking about), why do some people get so insistent that it's not us changing the environment? It might hurt some companies, but just like the nuclear issue, being safe isn't going to effect the vast majority of the people, including the people I've seen make these arguments.

Without getting into the issue at all, can anyone tell me why they feel so strongly for nuclear power, free market, or mans inability to effect his planet.

Now I really don't care about the issues, I know there are sides, I want to know about personal motivations. Do you really think your lights will go out or your bills will be higher without nuclear power? and if so, is that really so important to you to make you evangelic about it?

Same with the subject at hand. Maybe the facts will go one way, maybe the other (Not trying to start a fight, don't care about the facts right now), but what makes your response "Humans didn't cause it!" rather than "Damn, we better do something about it, build a solar shield or something!". (Actually, I'd guess many feel both responses, but always seem to reach for the "Humans didn't cause it" post first.

The only thing I can guess is that these are people of very strong personal morals who, if they felt that they were contributing to such a problem, would have to do something about it, so they convince themselves of a point that lets them do what it is they want to do and not feel guilty. I can see free marketeers doing the same thing--using it as an excuse to not care about others (which they may otherwise have to do) it doesn't apply to the nuclear thing in any way I can see (Honestly, this is the one that truly baffles me)...

Please reply if you have any insight into the issue because it drives me nuts. I'd really like to hear from an x-pro-nuke or x-free marketeer who has done some soul-searching and has some personal insight into why it was so important to them.

Because admitting we need to be careful is the first step to admitting there is a real problem, and if there's a real problem we all have to face some very uncomfortable changes. Much easier just to ignore it and carry on.

I'd like to nominate this for a really terrible piece of science reporting.

Number of probabilities reported: zero.

Number of fractional changes reported: zero.

I'm quite willing to believe that the loss of Arctic sea ice and the shrinking ice cap are significant and we should be worried (although not, of course, about the polar bears, who have weathered far greater climate fluxuations than this.) But this article gives none of the information that a rational person would require to make a judgment on the issue.

The science on global climate change is imperfect, but certainly not junk. The reporting on global climate change is another matter entirely...

Here's the full abstract. Note that 1 of 7 computer models showed total ice melt by 2040... the worst case scenario. Gotta love how the media grabs the flashy stuff.
Holland, Marika M.; Bitz, Cecilia M.; Tremblay, Bruno
Future abrupt reductions in the summer Arctic sea ice
Geophys. Res. Lett., Vol. 33, No. 23, L23503
http://www.agu.org/pubs/crossref/2006/2006GL028024 .shtml [agu.org]
Abstract
We examine the trajectory of Arctic summer sea ice in seven projections from the Community Climate System Model and find that abrupt reductions are a common feature of these 21st century simulations. These events have decreasing September ice extent trends that are typically 4 times larger than comparable observed trends. One eventexhibits a decrease from 6 million km2 to 2 million km2 in a decade, reaching near ice-free September conditions by 2040. In the simulations, ice retreat accelerates as thinning increases the open water formation efficiency for a given melt rate and the ice-albedo feedback increases shortwave absorption. The retreat is abrupt when ocean heat transport to the Arctic is rapidly increasing. Analysis from multiple climate models and three forcing scenarios indicates that abrupt reductions occur in simulations from over 50% of the models and suggests that reductions in future greenhouse gas emissions moderate the likelihood of these events.

The melting ``very definitely is caused in the climate model by increased greenhouse gas levels.''

So it's established that the current rate of greenhouse gas buildup will wreak havok in the computer model.

One of the things that confuses me about tidy feedback loops is that there is no mechanism for their reversal. If the factors that cause increased heat amplify themselves, why hasn't the planet died out from such a runaway loop? Because there are important variables and inputs outside the simplified scope of consideration.

I freely admit I have no idea how well validated their model is. It may be the shit, but it's tackling a formidible set of dynamics. There's nothing wrong with this (that's just science), but it is a bit less than quiet objectivity telling the mass media that X is going to happen. Epidemiologists seem more valid to argue that the H5N1 virus will wipe out a third of the globe (which some have done). Both are suggested by the evidence, but neither are as well documented outcomes as smoking or eating salmonella.

The media loves to seize on scare stories, however, because the public respond to it, so anyone who wants to have their study reported has to punch it up. As other posters have mentioned, each subsequent "boo!" headline desensitizes them to the message.

Part of the message, as I understand it, is that things are already bad, and getting worse. This state of affairs should lead people to activism without reminder. If people were suffering, they would react. Absent current intensity of the problem, one is left convincing people that things will get worse, and relatively soon, because most people aren't motivated by hazy, future problems. Much like it took rising gas prices for people to reconsider their fuel usage, it will take some tangible pain before people do anything about CO2 emissions.

I'll be curious to see what the world is really like in 30 years. I imagine that there will be some warming, with minimal, local effects on overall populations. People will adapt. There will continue to be wars and starvation in various places, and fingers will point in varied directions about it.

And it's also well documented that ice is increasing in areas like Greenland.

No it is not, according to RealClimate [realclimate.org]. Snowfall may be increasing at the interior of Greenland, but it's offset by an accelerated dumping of ice into the ocean at the periphery.

From RealClimate:

The critical point for Greenland is whether the increased rate of glacier motion more than compensates for the greater accumulation on the surface. While the broad picture of what is happening is consistent between these papers, the bottom

Take all the energy that the polar regions reflect because of sunlight, and instead add it to the ocean in polar regions.

That's the math they're saying they did, and the answer they came up with is : the polar cap melts fast!

If you don't want to buy it, do a counter study. As is, their results seem fairly clear and robust. Not saying that they're exactly right, but a counter argument needs to be more then you saying "NOOOOOOO".

I can think of a counter argument.The Gulf Stream is partially fuelled by the temperature gradient oop north (I'll be lazy and admit I forget the details) and has apparently already declined recently. This should kill it altogether. In the past, the North Pole being ice free has triggered ice ages.

How? Once the ice is gone, the sea can evaporate more easily which increases precipitation in the far north. A lot of this is snow. Eventually the icecap reasserts itself.

The Gulf Stream is partially fuelled by the temperature gradient oop north (I'll be lazy and admit I forget the details) and has apparently already declined recently. This should kill it altogether. In the past, the North Pole being ice free has triggered ice ages.

You want to talk about details? Let's talk about The Conveyor [grida.no]. As the ice melts in various locations it's going to change the conveyor, ultimately stop it and maybe even make it run in reverse. Global weather is going to be completely confused

Ever notice the color of clouds, they're white. More water in the oceans, warmer oceans = more clouds. You think this might be some sort of "balance"??Nooo, we can't have balance, and we can't include other factors in discussing global warming because the great mind of Al Gore says so.

More clouds = more rain, especially in deserts which will cause the desserts to bloom with all sorts of folliage and the great Sahara Forrest will be born, causing the CO2 levels to plummet, causing a huge global cooling perio

You seem to know a lot more about this than the real scientists... maybe you should let them know!Seriously though, you're as guilty as glossing over things as those you criticize. How do you expect these "great forests" to grow without any sunlight because the sky is constantly overcast? How will our crops grow?

But the real problem is, clouds don't just reflect sunlight, they also trap heat. And guess which one they are more effective at? You can take a look at our solar system for a clue: Mercury's peak t